Dark room for photographic purposes



Nov. 5, 1940. s. A. KRAUSER ET AL DARK ROOM FOR PHOTOGRAPHIC PURPOSESFiled Oct. 25, 1959 w mg k W v n m m 0 BYhM A 2 ATTORNEY Patented Nov.5, 1940 UNITED STATES 2,220,373 PATENT OFFICE DARK ROOM FOR PHOTOGRAPHICPURPOSES Application October 25, 1939, Serial No. 301,222

9 Claims.

5 printing, etc., and an object is to produce a new and improvedstructure of this character which can be compacted when not in use intoa relatively small space but which may be set up or assembled readilyand conveniently with the sections or panels connected together bysimple fasteners.

Another object is to provide a structure of the above character with anew and improved door mounting and joint connections so that the roomformed by the structure is substantially lightproof.

Other objects and advantages will hereinafter appear and, for purposesof illustration but not of limitation, the invention is shown on theaccompanying drawing in which Figure 1 is a perspective view of the darkroom in its assembled condition ready for use;

Figure 2 is an enlarged sectional view substantially on the line 22 ofFigure 1, showing par- 5 ticularly the connections between the side wallpanels and the manner of mounting the door;

Figure 3 is an enlarged sectional view substantially on the line 33 ofFigure 1;

Figure 4 is an enlarged sectional view substantially on the line 4-4 ofFigure 1;

Figure 5 is an enlarged sectional view substantially on the line 55 ofFigure 1; and

Figures 6 and '7 are fragmentary sectional views showing alternate formsof attaching side wall panels to make the structure substantiallylightproof.

The illustrated embodiment of the invention shown on Figure 1 comprisesa structure composed of side panels l and H, and panels I2 at oppositeends of the structure, it being understood that on the back side of thestructure, two side panels similar to the panel H] are employed. Thepanel I l as will hereinafter appear, is formed to provide a dooropening l3. Closing the top of the structure are panels l4 and i whichare substantially identical with each other and each of the panels l4and [5 have depending side flaps l6 and end flaps H, which are securedto the adjacent side wall panel by bolts l8 and wing nuts. One or moreholes [4 are formed in the top panels through which electric light cordmay be passed to the inside of the dark room. Covering the space betweenthe adjacent panels l4 and I5 is a strip [9 having end flaps at oppo- 5site ends and extending through the flaps l6 and 20 and the upright wallpanels are bolts I8 to which are attached wing nuts. Each of the panelsl4 and I5 are provided with fold lines 2| enabling these panels to befolded into a relatively small space.

The various panels above referred to are preferably formed of corrugatedboard, although it is to be understood that they may be formed fromother similar sheet materials which are capable of being folded in orderto compact the various sections of the structure into a relatively smallspace. As shown, each of the upright wall panels has two lines 22 ofscoring, thereby enabling them to be folded into a substantially Z-shape, when not in use in order to occupy a minimum amount of space.

As shown in Figure 2, each of the side and end wall panels is formedwith an inturned flap 23 along its vertical edge portion. Each flap 23extends inside the structure and abuts against the flap of the nextadjacent panel. In order to militate against the entrance of light alongthe abutting flaps 23, a substantially U-shaped sealing strip 24substantially oo-extensive with the abutting flaps 23 extends from topto bottom of the panels. As shown on Figure 2, the strip 24 is foldedover the outside of each pair of abutting flaps 23 and a series ofsimilar bolts l8 hold these parts together, wing nuts engaging theopposite ends of the bolts to afford a simple fastening device. From anexamination of Figure 2, it will be observed that the above describedjoint is employed not only between adjacent side wall panels but also atthe corners betwen the side wall panels and the adjacent end panels, theflexibility of the flaps enabling the positioning of the panels atsubstantially right angles to each other.

The side wall panel ii differs from the other side wall panels only inthat it is formed with a door opening and since the side and end wallpanels are all of the same size, the door opening may be positioned asdesired with respect to the sides or ends of the structure. The dooropening I3 is very simply formed by cutting the panel ll so that flaps25 may be folded inwardly upon the adjacent panel structure and held inplace by similar bolts I8 and wing nuts, a series of these being appliedfor the purpose. The material of the panel is severed so that flaps 25are not only provided along the vertical or up and down edges of thedoor opening but also along the top and bottom edges of the opening [3(see Figure 4). In this manner the entire edge of the door opening issatisfactorily re-enforced and the opening may be of any desired sizebut preferably of such size conveniently to admit a person to the insideof the dark room.

The door opening I3 is closed by a door 26 which conveniently is of thesame material as the rest of the structure and is likewise provided withlines 22' of scoring enabling it to be folded in to Z shape forconvenient packaging. As shown, the door consists of a panel portion 21,which is somewhat smaller than the side wall panel II but sufficientlylarge to close the door opening l3. The top, bottom and outer free edgeportions of the panel 2? are folded inwardly upon itself as indicated at28 in Figures 2, 4 and 5, the folds being held in place by bolts l8 andwing nuts, with the latter disposed on the inside of the door. Integralwith the opposite vertical edge portion is a hinge extension 29 whichprojects upwardly and downwardly beyond the horizontal edges of the doorto be substantially coextensive with the adjacent side wall panel II.The door panel 21 can swing relatively to the extension 29 along a lineof scoring 30 at the juncture between the panel 2'! and the extension29.

As shown particularly on Figure 2, the extension 29 extends around theoutside of the corner formed by the corner flap 23 on the panel H andhas its end portion disposed between the flaps 23 of the side wall panelI l and the end wall panel l2. Overlapping these end portions'is a strip24 above described and bolts l8 pass through the overlapping strip 24,end flaps 23, as well as door extension 29. It should also be noted thatthe bolts I8 which hold the flaps 25 of the door opening and which areadjacent to the end wall l2 also pass through the door extension 29 andassist in supporting the door in the desired position.

From the above description, it will be manifest that an exceedinglysimple and inexpensive dark room for photographic purposes is produced.The structure may be inexpensively made from corrugated board or othersimilar relatively inexpensive sheet materials. The several side and endwall panels are similarly formed with the exception of that panelproviding the door opening so that the die expense and cost ofmanufacture is kept as low as possible. A single die is suflicient forthe top panels and in view of the fact that these panels are inter- 40changeable, the assembly problem is made extremely simple. The simpleand convenient manner of fastening the panels together is of importance.It will be obvious that bolts having ordinary wing nuts are usedthroughout and the 45 joints between the panels are suflicient toeliminate any possibility of access of light to the inside. The door maybe mounted in any position desired and, manifestly, it is notnecessarythat it be mounted at the juncture of an end wall 50 and sidewall panels, because it can also be satisfactorily mounted if the panelsl and H, shown on Figure 2, are transposed.

Figure 6 illustrates an alternate form of connection between an end wallpanel |2a and a side 55 wall panel Illa. In this form, flaps on the edgeportions of the wall panels are dispensed with. L-shaped strips 30 and3| are arranged respectively 0n the inside and outside andbolts lBaconnect the strips 30 and 3| to the adjacent wall 60 panels. Thisconnection likewise is light-resistant and affords a relatively sturdyconnection. In the form shown on Figure 7, a wall panel I2!) is formedwith a substantially U-shaped flap extension 32 and received within theU is a flap 65 33 on the wall panel lllb. Bolts i8?) extend through thevarious thicknesses of material andretain the flaps in position. It willbe obvious that this joint between wall panels is likewise 70 efiectivein keeping light from the inside of the room.

It is to be understood that numerous changes in details of construction,arrangement and operation may be effected without departing from thespirit of the invention especially as defined 7 in the appended claims.

What we claim is:

l. A dark room structure for photographic purposes comprising aplurality of separate side Wall panels of bendable sheet material, toppanels, said panels having lines of scoring thereby to enable foldingsame for packaging, sealing strips at the joints of said side panelsoverlapping same, detachable fasteners securing said strips and adjacentpanels, one side panel having a door opening, a door of sheet materialfor closing said opening, and an extension on said door projecting intothe space between adjacent side wall panels and retained in place by thesame fasteners which secure together said panels.

2. A dark room structure as claimed in claim 1, comprising side flaps onthe side walls arranged in abutting relation to each other, a U-shapedsealing strip embracing abutting flaps, and fasteners common to saidsealing strip and flaps.

3. A dark room structure as claimed in claim 1, comprising flaps cutfrom one side wall panel and folded back upon said panel to provide saiddoor opening, and fasteners securing said flaps in place.

4. A dark room structure as claimed in claim 1, comprising dependingflaps at the edges of said top panels overlapping adjacent side wallpanels, and fasteners securing said flaps to said side wall panels.

5. A dark room structure as claimed in claim 1, comprising a door panelof a size to cover the door opening, said extension on one side of saiddoor panel having a longitudinal line of scoring providing a hinge,inturned flaps on the vertical edges of the side walls adapted to abutagainst each other, the end portion of said extension being disposedbetween said abutting flaps, and fasteners securing said end portion andflaps.

6. A dark room structure as claimed in claim 1, integral flaps on threesides of said door panel folded back upon the panel, fasteners securinsaid folded flaps in place, said extension on one side of said doorpanel having a longitudinal line of scoring providing a hinge, inturnedflaps on the vertical edges of the side walls adapted to abut againsteach other, the end portion of said extension being disposed betweensaid abutting flaps, and fasteners securing said end portion and flaps.

7. A dark room structure as claimed in claim 1, said extension on oneside of said door panel having a longitudinal line of scoring providinga hinge, inturned flaps on the vertical edges of the side walls adaptedto abut against each other, the end portion of said extension beingdisposed between said abutting fiaps, a U-shaped sealing strip embracingsaid abutting flaps, and fasteners securing said end portion, sealingstrip and flaps.

8. A dark room structure as claimed in claim 1, comprising a sealingstrip on the outside of the panel joints, and another sealing strip onthe inside of the panel joints, the fasteners passing through bothsealing strips and the panel disposed therebetween.

9. A dark room structure as claimed in claim 1, comprising a sealingstrip U-shaped in cross section integrally joined to one of the sidewall panels, the adjacent end portion of the other panel extendingbetween the arms of the U, and the fasteners passing through the severalplies to hold the parts in assembled relation.

STANLEY A. KRAUSER. PAUL W. MIESSLER.

